Fluid pressure applying apparatus



Aug. 9, 1932. G. A. SCHETTLER 1,870,384

FLUID PRES SURE APPLYING APPARATUS Filed Jan. 19, 1928 4 Sheets-Sheet 1 Agg. 9, 1932.

G. A. SCHETTLER 1,870,384

FLUID PRESSURE APPLYING APPARATUS 4 Sheets-Sheet 2 Filed Jan. '19, 1928 L lib P /0 7272 r A 66 J 64 E [raven/Z01 JLMFM Aug. 9, 1932. G A. SC-HETTLER FLUID PRESSURE APPLYING APPARATUS Filed Jan. 19, 1928 4 Sheets-Sheet 3 Z lnven tor Aug. 9, 1932. G. A. SCHETTLER 1,870,384

FLUID PRESSURE APPLYING APPARATUS Filed Jan. 19, 1928 4.Sheets-Sheet 4 h I. i

Patented Aug. 9, 1932 UNITED STATES PATENT, OFFICE GUSTAV ADOLF SCHETTLER, OF LEEDS, ENGLAND, ASSIGNOR TO THE TURNER TANNING MACHINERY COMPANY, OF PORTLAND, MAINE, A CORPORATION OF MAINE FLUID PRESSURE APPLYING APPARATUS Application filed January 19, 1928, Serial No. 247,876, and in Great Britain January 27, 1927.

i This invention relates to hydraulic apparatus and is illustrated as embodied in pressure applying means adapted for use in hydraulically operated machines of the type disclosed g in applicants copending application Serial No. 247,875, filed Jan. 19, 1928, such machines being specially constructed and arranged for smooth plating and embossing of hides, skins, leather and other similar pieces of work. It is to, to be understood, however, that the inven tion and various important features thereof may have other applications and uses.

It is an object of the invention to provide improved hydraulic pressure applying means in to facilitate the work of the. operator in obtaining a predetermined uniform pressure for the work. It is a further object of the invention to provide hydraulic apparatus of a relatively simple, yet durable construction, and 39 one that is economical in operation and capable of being easily controlled by the operator to secure the desired pressure practically instantaneously.

To these ends, and in accordance with important features of the invention, the illustrated apparatus comprises a pressure accumulator operable always at a predetermined pressure, a driven pump for charging the accumulator, and automatically acting 3Q means to control the supply of fluid from the pump to the accumulator. Since the pump is used only to charge the accumulator and to keep it charged under control of the automatic means, a reservoir of power is provided 3 5 always at a predetermined pressure for performing work. i

In the illustrated apparatus, the automatically acting means referred to is constructed and arranged to control the plungers of a Jg pump of a multiple plunger type during the charging and also during the discharging of the accumulator. As the accumulator becomes charged the plungers are automatically rendered inoperative one after another until, upon being fully charged, the pump is put entirely out of action. During operation of the apparatus to supply power for the performance of work, the accumulator is gradually discharged of its fluid contents and as this takes place a movable part of the accumulator sinks to a certain level and there becomes operative to bring the plungers of the pump into action again one after another to re charge the accumulator. This construction and arrangement for controlling the plungers of the pump has the advantage of providing an economical operation of the pump which is, indeed, out of operation most of the time. Conveniently, the accumultor is so constructed that the maximum pressure at which it may be charged may be regulated manually, for example, through transfer to a support of one or more weighted members that normally contribute their weight to the total Weight against which the pump operates in charging the accumulator.

An important feature of the invention resides in the provision of a primary or main valve which is hydraulically operated for opening and closing ports whereby the pressure applied to a given purpose may be instantaneously controlled. As illustrated, this valve comprises a plunger slidable within a housing and operable by connections to the accumulator. Preferably, and as shown, this valve controls not only the flow of fluid from the accumulator to the place where pressure is to be applied to work but also the flow of fluid to a reservoir or storage tank thereby releasing the pressure at the seat of operations. Hence, through this valve power may be both applied and released practically ins'tantaneously.

In the illustrated construction, the main valve is itself controlled by a control valve adapted to be operated manually so that the operator may decide the time of operation of power from the accumulator and also its duration.

These and other features of the invention and novel combinations of parts will now be described in detail and pointed out more particularly in the appended claims.

In the drawings, 7

Figure 1 is a side elevation of a hydraulic mechanism illustrating one embodiment of the invention;

Fig. 2 is an end elevation of the mechanism of Fig. 1;

Fig. 3 is a longitudinal section of thecontrol valve in its normal or Off position;

Fig. 4 is a longitudinal section, somewhat diagrammatic, of the main valve in its normal position;

Figs. 5 and 6 are views similar to Figs. 3 and 4 showing the respective valves in the positions occupied thereby when the pressure is on;

Fig. 7 illustrates a feature hereinafter described;

Fig. 8 is a sectional elevation of means em- I ployed to put the pump out otaction when the accumulator is. charged; and

Fig. 9, is a detail view of the starting lever for the control valve.

Referring first to Figs. 1 and 2, the illustratedhydraulic mechanism includes an accum'ulator A, a multiple plunger pump. P, a

. tank T for oil or water, a control valve C and a main valve M. The pump is connected with the accumulator through pipes 1 and 2 and an intermediate fitting The accumulator is connected withthe main valve M through the pipe 2, fitting 3 and a pipe 4. From the main valve a pipe 5 leads to the machine or apparatus to be operated. The main valve is also connected with. the tank T through a pipe 6, a safety valve 7, a pipe 8, T-piece 9 and a pipe 10. The control valve C is connected with the main valve by pipes 11, 12, with: the accumulator by a pipe 13, and with the oil tank by a pipe 14, the T- piece 9 and pipe 10 In order-that the construction and function of the main. valve may be clearly and: readily understood this valve is represented diagrammatically in Fig. 4. The said valve comprises a piston or plunger 15 slid'able in the bore 16 of a housing 17. The piston or plunger has a reduced portion 18 between its ends. Inlet and outlet ports 19', 20 are formed in the housing at which the pipe 4 leading from the accumulator and the pipe 5 leading to the machine or mechanism to be hydraulically operated are connected by bushings 21, 22, for the transmission of pressure from the accumulator to the machine or apparatus to be hydraulically operated. An exhaust port 23 is also provided at which the pipe 6 is connected by a bushing 24, the port 23 being opened, when required, to put the machine or apparatusinto communication with the tank T through the pipe 6 to 7 release thepre ssure to terminate a pressureapplying operation. Further, ports 25, 26

are provided near the opposite ends of the housing 17 at which the pipes 11 and 12 are connected by bushings 27, 28 for the transmission of pressure from the accumulator to the main valve by way of the control valve at one time, and for the discharge of oil from the main valve to the oil tank through the control valve at another time as will be more fully explained subsequently. The bore 16 is closed at opposite ends by screwed plugs 29, 30 which also serve as stops to limit the movement of the piston or plunger 15 in either direction.

The control valve C (Figs. 3 and 5). comprises a rotary member 31 working a houseing 32. The member 31 has a bore 33, transverse ports 34, 35, 36, 37, communicating with the bore 33, longitudinal grooves 38, 39, 40, 41, and circumferential grooves 42, 43. The ports 34, 35am formed at right angles to the ports 36, 37. The grooves 38', 39 are diametrically opposite to each other and both communicate with the groove The, grooves 40, 41 are likewise diametrically opposite to each other but are disposed at right angles to the grooves 38, 39, and communicate with the groove 43. A plug 44 closes the bore 33 at the outer end. The housing is provided with ports 45, 46, 47 for the transmission of pressure from the accumulator to the main valve and a port 48 for the passage of the oil from the ma n valve to the tank T. The pipes 11, 12, 13 and 14 are respectively connected to the housing at the corresponding ports by bushings 49, 50, 51,52.

When the control valve is turned to the Off position represented in Fig. 3, the ports 36, 37 are put into register' with the ports 45, 47. In the main valve the ports 20, 25, 26 are always open. Consequently one end of the plunger 15, i. e. theright hand end as viewed in Fig. 4, is subjected to pressure from the accumulator through the control valve and is thereby held in a posi-tion'wherein the port 19 is closed to shut off the pressure from the accumulator to the machine or apparatus to which the hydraulic mechanism is connected while the ports 20, 23-are open by reason of the reduced portion 18 of the plunger overlapping the same so that the machine or apparatus is in communication with the oil tank T and the pressure is relieved thus terminating a pressure applying operation.

When the control valve is turned infithei opposite direction (see the arrow in Fig. 3) the ports 34, 35 are brought into register with the ports 46,45 as" represented in Fig. 5'. The pressure is therefore removed from the aforesaid end ofv the plunger 15 and transferred to the opposite, i. e. left handendv The plunger thereupon moves to the right, i. e. into the position represented in: Fig.1 6, so as to close the port 23 and open the port 19, the port 20 remaining open so that pressure is l 10 the valve is turned in the other direction the grooves 10, e1 are brought into register with the ports 48, 47. Thus, whichever way the plunger moves a passage is provided from the main valve M to the oil tank T by Way of 15 the control valve C for the displacement of oil left in the housing 17 as the result of the previous operation of the plunger.

In the accumulator illustrated in the drawings, pressure is obtained by annular weights .0 53 (Fig. 1) supported by rods 5 1 fixed in a head 55 which presses upon the outer end of the accumulator piston or ram 56. The weights work up and down between the pil- 'lars 57 of the accumulator and these pllars have transverse holes 58 therein near their upper ends. The pressure is, of course Varied by varying the load on the suspension rods 5%. Thus when the pressure load is to be decreased one or more weights is, or are, held up at the top of the accumulator frame by means of pins inserted through the appropriate holes 58 under the weight or weights. See for example, Fig. 7, wherein a single weight 'i is shown supported by pins 59 passed through holes 58 in the pillars 57. In other words,

the accumulator works under a predetermined pressure measured by the weight of the weighted members 53 supported by the I piston 56 at any given time. The accumulator piston or ram 56 works in a cylinder 60 (Fig. 1) around which the weights are piled and whereby they are steadied, i. e. prevented from swinging. A pipe 61 is connected to j the cylinder 60 and the pipe has connected to it through the agency of various fittings 62. 63, 6 1, 65, 66 (Fig. 2) the pipes 2 and 13, i. e., from the pump P and control valve C respectively.

7 Control of the pump P is effected by means,

59 including spaced inclines or cams 67 carried by a moving part of the accumulator, as will be hereinafter described. Referring to Figs. 1, 2 and 8, the pump P included in the illus- "*'trated arrangement has three plungers, one

555 of which is shown at P in Fig. 8, and is rendered ineffective gradually, as the accumulator A become charged, by means of the inclines or cams 67 (Figs. 1 and 8) formed at different points on metal strips attached at opposite ends and at suitable distances apart to supports 68 carried by two of the weights 53. The inclines or cams vary in length, the uppermost one being the longest and the i lowermost the shortest, and are arranged to act successively upon corresponding levers 69 (Figs. 1, 2 and 8) situated in their paths. Since the cams 67 are of uniform height, the levers 69 are moved thereby through the same distances thus permitting uniformity of structure and operation of the valves and their operating parts. These levers are freely mounted upon a shaft 70 (Fig. 2) mounted in bearings 71 on the pump head, and are provided with rollers 7 2 and weights 73 (Fig. 8) whereby the rollers are held in contact with the cam strips 67. Each lever has connected to it a rod or link 74 (Figs. 2 and 8) which is also connected to a lever 75 fulcrumed at V 76 in a frame constituting part of the oil tank T. Each lever 75 is fitted with a block 77 hollowed to receive the lower end of a spring controlled fluted plunger 7 8 working through a gland 7 8a and acting upon a corresponding ball suction valve 79 of the pump P. The connection between each lever 69 and the corresponding rod 7 4 is preferably a yielding one constituted by a spring 80 (Figs. 2 and 8) and washers 81 held in posi tion by nuts 82. Thus during the upward movement of the accumulator weights 53 under pressure from the pump P, first the upper or longest cam, next the intermediate, and then the lowest or shortest cam or incline 67 acts through the corresponding lever 69 and intermediate connections to lift the suction valves 79 one after another so that the pressure exerted by the pump is decreased and finally the pump is rendered non-effective. In Fig. 1 the accumulator A is shown at the upper limit of its stroke in which position all three inclines or cams 67 are in action and the pump is inoperative. Fig. 8 shows the accumulator in its lowest position, to which it sinks, of course, when discharged, e. g., when the system is drained, thereby allowing the levers 69 to move under the influenceof their weights to bring the suction valves 79 into action again. Under these conditions, therefore, the full force of the pump is available quickly to charge up the accumulator to the required working pressure.

The pump P may be provided with a balance weight to keep it inactive, if desired, when the accumulator is discharged. Conveniently and as shown in Fig. 8, a lever 83 carrying a weight 84 is fixed on one end of the shaft 70 and the latter has recesses 85 formed therein to correspond with the levers 69. Each of these levers is fitted with a. screw 86 which is offset with respect to the axis of the shaft and enters the corresponding recess at one end thereof to make contact with the shaft. By turning the lever 83 in one direction, i. e., in the direction of the arrow in Fig. 8, the shaft 70 is caused to press upon the screws 86 and thereby operate the levers 69 to lift the suction valves 79. Upon reverse movement of the lever 83 the levers 69 are released and the suction valves 79 return to their normal positions.

Adjustable stops 87, 88 are provided in a carrier 89 attached to the pump head to limit the movements of the lever 83. The stop 88 engages a member 90 loose on the shaft and with which 2. lug or projection 91 on the lever 83 makes contact when the latter, is turned sufliciently to lift the suction valves. The other stop engages the said lug or projection 91 when the lever 83 is turned back to its normal position. The weight is, of course, effect ve to hold the lever in either of its two .tight joint in its housing when screwed back into inoperative position. The illustrated mechanism may also be equipped with a safe ty valve 95 (Fig. 2) which latter is shown associated with the fitting 7 When the hydraulic mechanism above described, comprising the accumulator, the pump, the main and control valves, is employed, in conjunction with the machine of the aforesaid copending application, for (3X- ample, the pump is conveniently cared, by a gear or crank shaft 102 of tee pump, to driving shaft 104 of the machine through a pinion 106 fixed to the shaft and is adapted for rotation in either direction. Thus when the said machine is put into motion the pump starts, although it may not, when started, operate, as this will depend upon the condition of the accumulator as already described.

Any suitable means may be employed for operating the control valve C. For example, the rotary member 31 of the valve C may be turned by automatically operated gearing, as fully set forth in my copending application Serial No. 247,875. As illustrated, means under the control of the operator is provided for operating the valve C, thereby enabling the operator to determine the time of operation ofthe hydraulic apparatus and also the duration of-such operation. For this purpose the rotary member 31 of the valve C is provided with an extension 124 (Figs. 2, 3 and 9) rigid therewith and having fastened to its outer end a beveled gear 125 arranged to be constantly in mesh. with a segmental bev e'led gear member 12505 fixedly secured to a rock shaft126, the latter being furnished with an operating handle 128. 7' Associated with the handle 128 is a sector 130 having a slot in which'the handle 128 moves, shoulders at each end of the slot serving to limit the movement otthe handle in either direction. Conveniently the sector 130 carries the indications On and Off (Fig. 2). In the On position of the handle 128, the valve C is exercising control of the main valve M to effect the application of hydraulic pressure to the machine or apparatus with which thehydraulic apparatus is being used. When it is desired to release the pressure the handle sure from the accumulator A and as promptrelease oi? the pressure. When the handle 128 is in the Off position the main valve M is conditioned to discharge a portion of the fluid under pressure into the reservoir or tank thereby instantly releasing the pressure to terminate a pressure applying operation. Vv hen the handle 128 is moved to the On position, the main valve M is condi' tioned to provide a direct connection between the accumulator A and the machine" to be ydraulically operated, the transmission of pressure being practically instantaneous. When the operator desires to change the pres-- sure at which the accumulator A operates, he lifts one or more of the weighted members 53 and locks it, or them, in raised position by means of pins 59 inserted through holes in the standards 57, as indicated in Fig. 7 of the drawings. Because of the control of the plunger-s of the pump exercised by the cams- 6'7, the accumulator operates the greater part of the time with the pump inactive. As soon, however, as the accumulator sinks to a certain level, after repeated operations during which a small amount of the pressure fluid is lost at each operation, the plungers are caused to become operative again. to recharge the accumulator. lVhen the accumulator has been charged, the plungers are put out of action in the manner described, so that repeated pressure applying operations may take place without using the pump.

Having described my invention, what I claim as new and desire to secure by Letters Patent of the United States is:

1. In a hydraulic pressure applying apparatus, a pump having a plurality of plung ers and associated suction valves an' accumulator having connections with the pump and arranged to be charged by the latter, said accumulator comprising a member carried by the accumulator and movable therewith during the charging and discharging 2. In a hydraulic pressure applying apparatus, a pump having a plurality oi: plungers and associated suction valves, an accumulator having connections with the pump and arranged to be charged by the latter, said accumulator comprising a member movable during the charging and discharging of the accumulator, levers operatively connected to the suction valves, and cams on the movable member of the accumulator arranged in spaced relation in the direction of the movement of the accumulator member to operate directly upon the levers in succession for controlling the suction valves to render the suction valves one after another inefiective, and subsequently in the reverse order efiective to control the operation of the plungers.

3. In an hydraulic pressure applying apparatus, a pump having a plurality of plungers and associated suction valves, an accumulator having connections with the pump and arranged to be charged by the latter, said accumulator comprising a member movable during the discharging and charging of the accumulator, cams connected to said member and arranged in a series extending in the direction of movement of the accumulator member, and levers arranged to be operated directly by the cams while the accumulator member is moving to its lowest position, the said levers being operable in one direction directly by said cams to render the plungers effective one after another during the continued descent of the accumulator member, said cams being of different lengths in the direction of travel of said accumulator member, whereby upon reverse movement of the accumulator member the cams effect operation of the levers in the reverse order to render the plungers ineffective one after another.

4. In an hydraulic pressure applying apparatus, a pump having a plurality of plungers and associated suction valves, an accumulator having connections with the pump and arranged to be charged by the latter, said accumulator comprising a member movable during the charging and discharging of the accumulator, levers normally controlled by the member for operating the suction valves alternately to closed and to open position and thus regulating the action of the plungers so that the plungers become effective as the accumulator approaches its discharged condition and subsequently ineffective as the accumulator approaches charged condition, and a manually operable member freely movable with respect to the levers for holding said levers in valve opening position whereby the pump is thrown out of action.

5. In an hydraulic pressure applying apparatus, a pump having a plurality of plungers, an accumulator having connections with the pump and arranged to be charged by the latter, said accumulator comprising a mem- GUSTAV ADOLF SCHETTLER. 

